This is a collaborative proposal between the California Institute of Technology, the University of California at Los Angeles, and the University of Southern California, to establish a computer graphics facility for the use of structural molecular biologists at these three institutions and elsewhere in the Los Angeles Basin, particularly the University of California at Riverside (McPherson, Jurnak) and California State University at Northridge (Hsu). Among the applications envisioned for the facility are: (a) Model-building and X-ray analysis of small DNA and complexes with intercalators and drugs, (b) Display and fitting of difference Patterson maps during heavy atom searches, (c) Fitting structure to density ("electronic Richards box"), (d) Monitoring refinement of macromolecules, (e) Studies of surface interactions and recognition between macromolecules (f) Theoretical studies of protein folding, enzyme-substrate interactions, and primary processes in vision, with display of conformations and potential energy surfaces. Among the specific problems to be examined are: CGCG and CCGG complexes with bismethidiumspermin and cis-dichlorodiaminoplatinum (II), lac repressor-operator complex, interactions of cytochrome oxidase, c551 and azurin, glutamine synthetase, melittin, E. coli DNA ligase, the phycobiliproteins, gene 5 protein, Tu elongation factor, and pencillopepsin.